Update assistant config UI (#15630)

![CleanShot 2024-08-01 at 12 55
01@2x](https://github.com/user-attachments/assets/f9ed44ba-6bff-4805-ad71-2e3538315e57)

- Remove assisstant_description for now.
- Updates assistant config UI
- Updates Ollama and zed.dev provider UIs
- Updates download icon

Release Notes:

- N/A

---------

Co-authored-by: Marshall Bowers <1486634+maxdeviant@users.noreply.github.com>
Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>

assets/icons/download.svg

@@ -1,10 +1 @@
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+<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="lucide lucide-download"><path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/><polyline points="7 10 12 15 17 10"/><line x1="12" x2="12" y1="15" y2="3"/></svg>